The sublime moment of cooking, though, is really the moment when nature becomes culture, stuff becomes things. It is the moment when the red onions have been chopped and the bacon has been sliced into lardons and the chestnuts have been peeled, and they are all mijoteing together in the pot, and then--a specific moment--the colors begin to change, and the smells gather together just at the level of your nose. Everything begins to mottle, bend from raw to cooked. The chestnuts, if you're doing chestnuts, turn a little damp, a little weepy. That's what they do; everything weeps.